1. Field of the Invention
This invention relates to a unique wick used with a reusable burner device of the liquid fuel type which wick is a composite constructed of parallel strands of fiberglass, which are held together by thermal conducting wire to provide a wick of predetermined width and height which realizes consistent fuel combustion.
2. Description of the Prior Art
Burner devices which provide heat to warm or cook food or liquids such as in a chafing dish are known in the art. Most prior art devices are commonly of the "canned heat" type. The two most widely used types of fuels for such devices are solid or liquid. The solid fuel is a flammable semi-solid (impregnated chemical gel and/or liquid saturated inert substrate); and the liquid, a refined, specific use, flammable type. The flames produced by burners using these fuels are:
First, a flame above and on the surface of the exposed fuel of an open fuel reservoir, the height determined by the surface of the remaining fuel and the open reservoir being the burner assembly (solid type such as alcohol gel);
Second, a flame on and above a surface of fixed area, the height constituted by a hole in the top or lid of the reservoir exposing a non-consumable substrate totally saturated and butted tightly against the underside of the top or lid which functions as the burner assembly (solid type such as impregnated chemical gel and/or liquid saturated inert substrate); and
Third, a flame on and above a saturated surface of fixed area and height on a non-consumable wick totally saturated, protruding through, and snugly retained by, an aperture in a portion of a reservoir cover or seal, which is the burner assembly (liquid fuel).
A major requirement in the design and manufacture of these devices is that they maintain a consistent heat output at the surface of the cooking or warming vessel for a specified amount of time. In general, devices, which use either type of fuel, produce a flame with characteristics dependent on the fuel vaporization surface, fuel supply at the surface, and introduction of oxygen via normal aspiration induced by the flame. The heating value of the flame and the time that it will burn is a result of fuel feed control, the characteristics of the fuel, and the flame size, all of which are determined by research and testing and whose fidelity is protected and controlled during manufacture of the device. The end result of this effort, and heretofore desired, is a very consistent product having a fixed heat rate (BTU/hour) and consequently a fixed burn time. The first solid fuel device does not particularly lend itself to consistent heating of vessels, because the origin of the flame changes position vertically as does the flame's steadiness, and its quality diminishes as it burns deeper down into the reservoir.
The second solid fuel type burner is an improvement over the first; however, the liquid fuel device is more desirable, due to its flame consistency, high heat, safety, and is reusable.
A well known type of solid product is "Sterno", which includes a metal can with a removable top with exposed alcohol gel that is lit to provide a flame. While this product will heat food and liquids it is hazardous, with a low flash point of 55 degrees Fahrenheit and therefor must be treated with great care. The "Sterno" product also gives off odor as it burns, the wick decomposes, the fuel evaporates and is not reusable, the container heats up and can set a fire if tipped over. The flame height and intensity will also vary as the fuel is consumed. Similar disadvantages are found in the second form of solid fuel burning devices.
Examples of devices which provide flame, and are used for illumination, or to produce heat are disclosed in the U.S. Patents to Giangiulio U.S. Pat. Nos. 3,885,905 and 4,025,290; Giangiulio et al. U.S. Pat. No. 4,464,109 and Menter et al. U.S. Pat. No. 4,611,986. However, none of these devices provides all the desired characteristics.
The device of the invention provides a consistent high heat flame, of preset height during its operating life, is non-hazardous to transport and use, is reusable, is odorless, whose fuel does not evaporate, the products of combustion are non-toxic, and which device in addition enjoys other advantages.